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O'Fallon, IL

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O'Fallon, IL Weather

Today WinterCast Local {stormName} Tracker Hourly 10-Day Radar MinuteCast® Monthly Air Quality Health & Activities

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8 PM

80°

RealFeel® 89°

Very Warm

RealFeel Guide

Very Warm

82° to 89°

Older adults, infants, and those with sensitive medical conditions should minimize outdoor activity, especially in the sunshine.

47%

Thunderstorms

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

Heat Index85°

WindSE 5 mph

Air QualityPoor

Wind Gusts6 mph

Humidity92%

Indoor Humidity92% (Extremely Humid)

Dew Point77° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover80%

Rain0.01 in

Visibility10 mi

Cloud Ceiling30000 ft

9 PM

79°

RealFeel® 87°

Very Warm

RealFeel Guide

Very Warm

82° to 89°

Older adults, infants, and those with sensitive medical conditions should minimize outdoor activity, especially in the sunshine.

43%

Thunderstorms

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

Heat Index83°

WindS 5 mph

Air QualityPoor

Wind Gusts5 mph

Humidity87%

Indoor Humidity87% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover91%

Visibility6 mi

Cloud Ceiling4000 ft

10 PM

79°

RealFeel® 87°

Very Warm

RealFeel Guide

Very Warm

82° to 89°

Older adults, infants, and those with sensitive medical conditions should minimize outdoor activity, especially in the sunshine.

41%

Partly cloudy

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

Heat Index81°

WindSSW 5 mph

Air QualityPoor

Wind Gusts5 mph

Humidity88%

Indoor Humidity88% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover49%

Visibility10 mi

Cloud Ceiling30000 ft

11 PM

76°

RealFeel® 85°

Very Warm

RealFeel Guide

Very Warm

82° to 89°

Older adults, infants, and those with sensitive medical conditions should minimize outdoor activity, especially in the sunshine.

34%

Intermittent clouds

Heat Advisory

11:00 AM Tuesday - 8:00 PM Saturday

WindS 5 mph

Air QualityPoor

Wind Gusts5 mph

Humidity94%

Indoor Humidity94% (Extremely Humid)

Dew Point75° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover51%

Visibility10 mi

Cloud Ceiling30000 ft

Hourly Weather Forecast for O'Fallon

AccuWeather's hourly forecast for O'Fallon provides hour-by-hour temperatures, RealFeel® Temperature, and precipitation probability through the next 10 days. The current hour shows 80° with a RealFeel® of 89°, thunderstorms with a 47% chance of precipitation. Each hourly forecast includes wind speed, humidity, air quality, UV index, and the AccuLumen Brightness Index™, AccuWeather's measure of perceived outdoor light intensity. Forecasts are generated by proprietary systems developed by AccuWeather meteorologists since 1962.

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